Determinants of In-Hospital Mortality Among Type 2 Diabetes Mellitus-Related Admissions in a Tertiary Teaching Hospital

<b>Background/Objectives</b>: Globally, type 2 diabetes mellitus (T2DM) accounts for about 90% of diabetes cases and contributes to hospital admissions and mortality in Malaysia. Identifying the determinants of in-hospital mortality is crucial for improving clinical management and resource allocation. This study aims to determine the clinical and disease-related determinants of in-hospital mortality among T2DM-related admissions in a tertiary teaching hospital. <b>Methods</b>: A cross-sectional study at Hospital Canselor Tuanku Muhriz (HCTM) in Kuala Lumpur involving 2838 T2DM-related admissions from the hospital casemix database. Demographic data, complications, disease group, length of stay, and number of diagnoses were analyzed. Logistic regression assessed factors associated with in-hospital mortality among T2DM-related admissions. <b>Results</b>: The in-hospital mortality rate among T2DM-related admissions was 4.2%. T2DM-related admissions resulting in in-hospital death involved individuals with a higher mean age (67.72 years, SD 12.06) compared to admissions that did not result in death (65.11 years, SD 11.03). Significant determinants of mortality included infections and parasitic diseases (aOR = 8.042; 95% CI: 2.999, 21.569; <i>p</i> < 0.001), respiratory system (aOR = 3.004; 95% CI: 1.192, 7.571; <i>p</i> = 0.020), hepatobiliary/pancreatic (aOR = 3.674; 95% CI: 1.143, 11.871; <i>p</i> = 0.029), and central nervous system (aOR = 3.484; 95% CI: 1.236, 9.826; <i>p</i> =0.018) conditions, and severity level 3 (aOR = 2.994; 95% CI: 1.464, 6.221; <i>p</i> = 0.003). Each additional diagnosis increased the mortality risk (aOR = 1.107; 95% CI: 1.032, 1.189; <i>p</i> = 0.005). <b>Conclusions</b>: Mortality among hospitalized T2DM-related admissions is driven by severe infections, respiratory, hepatobiliary, and neurological conditions, together with overall disease burden. Early identification of high-risk clinical presentations and a timely multidisciplinary approach may reduce preventable deaths among T2DM patients.